Refrigerants containing (e)-1,1,1,4,4,4-hexafluorobut-2-ene

ABSTRACT

A composition including (E)-1,1,1,4,4,4-hexafluorobat-2-ene as a mixture with at least one hydrocarbon, hydrofluorocarbon or fluoroolefin compound having a boiling point less than or equal to −12° C., and also to the use of this composition as a heat transfer fluid. A process for reducing the environmental impact of heat-transfer equipment including a vapor compression circuit containing an initial heat-transfer fluid, said process comprising a step replacing the initial heat-transfer fluid in the vapor compression circuit with a final heat-transfer fluid, the final heat-transfer fluid having a GWP which is lower than the initial heat-transfer fluid, wherein the final heat-transfer fluid is the above composition.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. application Ser. No.13/989,437, filed on Jun. 13, 2013, which is a U.S. national stage ofInternational Application No. PCT/FR2011/052589, filed on Nov. 8, 2011,which claims the benefit of French Application No. 1059728, filed onNov. 25, 2010. The entire contents of each of U.S. application Ser. No.13/989,437, International Application No. PCT/FR2011/052589, and FrenchApplication No. 105972 are hereby incorporated herein by reference intheir entirety.

FIELD OF THE INVENTION

The present invention relates to compositions containing(E)-1,1,1,4,4,4-hexafluorobut-2-ene as a mixture with at least one otherhydrocarbon compound or hydrocarbon derivative, and the use thereof asheat-transfer fluids.

TECHNICAL BACKGROUND

Fluids based on fluorocarbon compounds are largely used invapor-compression heat-transfer systems, in particular air conditioning,heat pump, refrigeration and freezing devices. These devices have incommon the fact that they are based on a thermodynamic cycle comprisingthe vaporization of the fluid at low pressure (in which the fluidabsorbs heat); the compression of the vaporized fluid up to a highpressure; the condensation of the vaporized fluid to liquid at highpressure (in which the fluid releases heat); and the expansion of thefluid in order to complete the cycle.

The choice of a heat-transfer fluid (which may be a pure compound or amixture of compounds) is dictated, on the one hand, by the thermodynamicproperties of the fluid, and on the other hand, by additionalconstraints. Thus, one particularly important criterion is that of theimpact of the fluid under consideration on the environment. Inparticular, chlorinated compounds (chlorofluorocarbons andhydrochlorofluorocarbons) have the disadvantage of damaging the ozonelayer. Henceforth, generally non-chlorinated compounds such ashydrofluorocarbons, fluoroethers and fluoroolefins are thereforepreferred to them.

It is, however, necessary to develop other heat-transfer fluids thathave a global warming potential (GWP) lower than that of theheat-transfer fluids currently used, and that have equivalent orimproved performance levels.

Document WO 2007/053697 describes fluoroolefin-based compositions invarious uses, and in particular as heat-transfer fluids. The documentmentions 1,1,1,4,4,4-hexafluorobut-2-ene.

Document WO 2008/134061 describes azeotropic or azeotrope-likecompositions comprising (Z)-1,1,1,4,4,4-hexafluorobut-2-ene incombination with methyl formate, pentane, 2-methylbutane,1,1,1,3,3-pentafluorobutane, trans-1,2-dichloroethylene or1,1,1,3,3-pentafluoropropane.

Document WO 2008/154612 describes azeotropic or azeotrope-likecompositions comprising (E)-1,1,1,4,4,4-hexafluorobut-2-ene incombination with methyl formate, n-pentane, 2-methylbutane,trans-1,2-dichloroethylene, 1,1,1,3,3-pentafluoropropane, n-butane orisobutane.

Document WO 2010/055146 describes fluoroolefins and the process forproducing them. The document mentions in particular(E)-1,1,1,4,4,4-hexafluorobut-2-ene.

Document WO 2010/100254 describes tetrafluorobutenes, optionally as amixture with hexafluorobutenes, and the use thereof in variousapplications, including heat transfer.

However, there is still a need to develop other heat-transfer fluidswhich have a relatively low GWP and which are capable of replacing theusual heat-transfer fluids.

In particular, it is desirable to develop other heat-transfer fluidswith a low GWP which are azeotrope-like and/or which exhibit good energyperformance levels compared with usual heat-transfer fluids (such asisobutane) and/or improved energy performance levels compared with theknown heat-transfer fluids with a low GWP (such as1,3,3,3-tetrafluoropropene).

SUMMARY OF THE INVENTION

The invention relates first and foremost to a composition comprising(E)-1,1,1,4,4,4-hexafluorobut-2-ene as a mixture with at least onehydrocarbon, hydrofluorocarbon, ether, hydrofluoroether or fluoroolefincompound having a boiling point less than or equal to −12° C.

According to one embodiment, the compound is chosen from1,3,3,3-tetrafluoropropene, 2,3,3,3-tetrafluoropropene,3,3,3-trifluoropropene, 1,1,1,2-fluoro-ethane, 1,1-difluoroethane,difluoromethane, pentafluoroethane, propane and dimethyl ether, andmixtures thereof.

According to one embodiment, the composition consists of a mixture of:

-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene and a compound chosen from    1,3,3,3-tetrafluoropropene, 2,3,3,3-tetrafluoropropene,    3,3,3-trifluoropropene, 1,1,1,2-tetrafluoroethane,    1,1-difluoroethane, difluoromethane, pentafluoroethane, dimethyl    ether and propane; or-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene and two compounds chosen from    1,3,3,3-tetrafluoropropene, 2,3,3,3-tetrafluoropropene,    3,3,3-trifluoropropene, 1,1,1,2-tetrafluoroethane,    1,1-difluoroethane, difluoromethane, pentafluoroethane, propane,    dimethyl ether and isobutane.

According to one embodiment, the composition comprises and preferablyconsists of a mixture of:

-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene and 1,3,3,3-tetrafluoropropene;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene and 2,3,3,3-tetrafluoropropene;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene and 3,3,3-trifluoropropene;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene and 1,1,1,2-tetrafluoroethane;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene and 1,1-difluoroethane;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene and difluoromethane;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene and propane;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, 1,1,1,2-tetrafluoroethane and    1,3,3,3-tetrafluoropropene;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, 1,1,1,2-tetrafluoroethane and    2,3,3,3-tetrafluoropropene;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, 1,1,1,2-tetrafluoroethane and    1,1-difluoroethane;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, 1,1,1,2-tetrafluoroethane and    3,3,3-trifluoropropene;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, 1,1,1,2-tetrafluoroethane and    isobutane;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, 1,1,1,2-tetrafluoroethane and    propane;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, isobutane and    1,3,3,3-tetrafluoropropene;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, isobutane and    2,3,3,3-tetrafluoropropene;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, isobutane and    1,1-difluoroethane;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, isobutane and propane;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, 3,3,3-trifluoropropene and    2,3,3,3-tetrafluoropropene;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, 3,3,3-trifluoropropene and    1,3,3,3-tetrafluoropropene;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, 3,3,3-trifluoropropene and    isobutane;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, 3,3,3-trifluoropropene and    1,1-difluoroethane;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, 3,3,3-trifluoropropene and    propane;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, 1,3,3,3-tetrafluoropropene and    2,3,3,3-tetrafluoropropene;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, 1,3,3,3-tetrafluoropropene and    propane;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, 1,3,3,3-tetrafluoropropene and    1,1-difluoroethane;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, 2,3,3,3-tetrafluoropropene and    propane;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, 2,3,3,3-tetrafluoropropene and    1,1-difluoroethane;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, 1,1-difluoroethane and propane;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, pentafluoroethane and    1,3,3,3-tetrafluoropropene;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, pentafluoroethane and    2,3,3,3-tetrafluoropropene;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, pentafluoroethane and    3,3,3-trifluoropropene;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, pentafluoroethane and    1,1-difluoroethane;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, pentafluoroethane and    difluoromethane;-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene, pentafluoroethane and    1,1,1,2-tetrafluoroethane.

According to one embodiment, the difference between the liquidsaturation pressure and the vapor saturation pressure of the compositionat a temperature of −5° C. is less than or equal to 10% of the liquidsaturation pressure, and preferably the composition comprises orconsists of:

-   from 1% to 8% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene and from 92% to    99% of 2,3,3,3-tetrafluoropropene; or-   from 1% to 12% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene and from 88%    to 99% of 1,3,3,3-tetrafluoropropene; or-   from 1% to 9% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene and from 91% to    99% of 1,1,1,2-tetrafluoroethane; or-   from 1% to 6% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene and from 94% to    99% of difluoromethane; or-   from 1% to 17% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene and from 83%    to 99% of 1,1-difluoroethane; or-   from 1% to 26% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene and from 74%    to 99% of propane; or-   from 1% to 10% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene and from 90%    to 99% of 3,3,3-trifluoropropene; or-   from 1% to 10% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 1% to    98% of 1,1,1,2-tetrafluoroethane and from 1% to 98% of    1,3,3,3-tetrafluoropropene; or-   from 1% to 8% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 1% to 98%    of 1,1,1,2-tetrafluoroethane and from 1% to 98% of    2,3,3,3-tetrafluoropropene; or-   from 1% to 15% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 1% to    98% of 1,1,1,2-tetrafluoroethane and from 1% to 98% of    1,1-difluoroethane; or-   from 1% to 8% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 1% to 98%    of 2,3,3,3-tetrafluoropropene and from 1% to 98% of    3,3,3-trifluoropropene; or-   from 1% to 8% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 1% to 98%    of 1,1,1,2-tetrafluoroethane and from 1% to 98% of    3,3,3-trifluoropropene; or-   from 1% to 8% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 1% to 98%    of 2,3,3,3-tetrafluoropropene and from 1% to 98% of    1,3,3,3-tetrafluoropropene; or-   from 1% to 20% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 1% to    30% of 1,1,1,2-tetrafluoroethane and from 50% to 98% of propane; or-   from 1% to 20% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 1% to    98% of 2,3,3,3-tetrafluoropropene and from 1% to 98% of propane; or-   from 1% to 13% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 1% to    98% of 2,3,3,3-tetrafluoropropene and from 1% to 98% of    1,1-difluoroethane; or-   from 1% to 15% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 1% to    98% of 1,3,3,3-tetrafluoropropene and from 1% to 98% of    1,1-difluoroethane; or-   from 1% to 20% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 1% to    98% of 1,3,3,3-tetrafluoropropene and from 1% to 98% of propane.

According to one embodiment, the composition comprises and preferablyconsists of:

-   from 10% to 50% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene and from 50%    to 90% of 1,3,3,3-tetrafluoropropene, preferably from 30% to 40% of    (E)-1,1,1,4,4,4-hexafluorobut-2-ene and from 60% to 70% of    1,3,3,3-tetrafluoropropene; or-   from 55% to 95% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene and from 5%    to 45% of 1,1,1,2-tetrafluoroethane; or-   from 1% to 98% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 1% to    98% of 2,3,3,3-tetrafluoropropene and from 1% to 50% of    1,1,1,2-tetrafluoroethane, preferably from 2% to 60% of    (E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 2% to 93% of    2,3,3,3-tetrafluoropropene and from 5% to 50% of    1,1,1,2-tetrafluoroethane and more particularly preferably from 5%    to 45% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 11% to 86% of    2,3,3,3-tetrafluoropropene and from 9% to 44% of    1,1,1,2-tetrafluoroethane; or-   from 1% to 98% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 1% to    98% of 1,3,3,3-tetrafluoropropene and from 1% to 40% of    1,1,1,2-tetrafluoroethane, preferably from 2% to 40% of    (E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 20% to 93% of    1,3,3,3-tetrafluoropropene and from 5% to 40% of    1,1,1,2-tetrafluoroethane and more particularly preferably from 2%    to 35% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 33% to 89% of    1,3,3,3-tetrafluoropropene and from 9% to 32% of    1,1,1,2-tetrafluoroethane.

The invention also relates to the use of the composition above, as aheat-transfer fluid.

The invention also relates to a heat-transfer composition comprising thecomposition above and also one or more additives chosen from lubricants,stabilizers, surfactants, tracers, fluorescent agents, odorous agentsand solubilizing agents, and mixtures thereof.

The invention also relates to heat-transfer equipment comprising a vaporcompression circuit containing a composition as described above asheat-transfer fluid or containing a heat-transfer composition asdescribed above.

According to one embodiment, the equipment is chosen from mobile orstationary heat-pump heating, air conditioning, refrigeration andfreezing equipment and Rankine cycles.

The invention also relates to a process for heating or cooling a fluidor a body by means of a vapor compression circuit containing aheat-transfer fluid, said process successively comprising evaporation ofthe heat-transfer fluid, compression of the heat-transfer fluid,condensation of the heat-transfer fluid and expansion of theheat-transfer fluid, wherein the heat-transfer fluid is a composition asdescribed above.

According to one embodiment, this process is a process for cooling afluid or a body, wherein the temperature of the fluid or of the bodycooled is from −15° C. to 15° C., preferably from −10° C. to 10° C. andmore particularly preferably from −5° C. to 5° C.; or is a process forheating a fluid or a body, wherein the temperature of the fluid or ofthe body heated is from 30° C. to 90° C., preferably from 35° C. to 60°C. and more particularly preferably from 40° C. to 50° C.

The invention also relates to a process for reducing the environmentalimpact of heat-transfer equipment comprising a vapor compression circuitcontaining an initial heat-transfer fluid, said process comprising astep of replacing the initial heat-transfer fluid in the vaporcompression circuit with a final heat-transfer fluid, the finalheat-transfer fluid having a GWP lower than the initial heat-transferfluid, in which the final heat-transfer fluid is a composition asdescribed above.

The present invention makes it possible to overcome the drawbacks of theprior art. It more particularly provides heat-transfer fluids with a lowGWP, capable of replacing the usual heat-transfer fluids.

In particular, in certain embodiments, the invention providesazeotrope-like heat-transfer fluids. In certain embodiments, theinvention provides heat-transfer fluids which have good energyperformance levels compared with usual heat-transfer fluids and/or haveimproved energy performance levels compared with known heat-transferfluids with a low GWP (in particular compared with1,3,3,3-tetrafluoropropene).

This is accomplished by virtue of mixtures comprising, on the one hand,1,1,1,4,4,4-hexafluorobut-2-ene in trans form and, on the other hand, atleast one hydrocarbon, hydrofluorocarbon or fluoroolefin compound havinga boiling point less than or equal to −12° C. This compound ispreferably chosen from 1,3,3,3-tetrafluoropropene,2,3,3,3-tetrafluoropropene, 3,3,3-trifluoropropene,1,1,1,2-tetrafluoroethane, 1,1-difluoroethane, difluoromethane andpropane, and mixtures thereof.

The compositions according to the invention have an improved volumetriccapacity compared with the compositions disclosed in document WO2008/154612 (in which the compounds combined with(E)-1,1,1,4,4,4-hexafluorobut-2-ene have a boiling point greater than−12° C.).

The compositions according to the invention also have a volumetriccapacity that is greater than analogous compositions in which the(E)-1,1,1,4,4,4-hexafluorobut-2-ene is totally or partially replacedwith (Z)-1,1,1,4,4,4-hexafluorobut-2-ene.

DESCRIPTION OF EMBODIMENTS OF THE INVENTION

The invention is now described in greater detail and in a nonlimitingmanner in the description which follows.

The compounds used in the context of the invention are denoted asfollows:

-   (E)-1,1,1,4,4,4-hexafluorobut-2-ene: HFO-E-1336mzz;-   1,3,3,3-tetrafluoropropene: HFO-1234ze;-   2,3,3,3-tetrafluoropropene: HFO-1234yf;-   3,3,3-trifluoropropene: HFO-1243zf;-   1,1,1,2-tetrafluoroethane: HFC-134a;-   1,1-difluoroethane: HFC-152a;-   difluoromethane: HFC-32;-   pentafluoroethane: HFC-125;-   propane: HC-290;-   isobutane: HC-600a;-   dimethyl ether: DME.

Unless otherwise mentioned, throughout the application, the proportionsof compounds indicated are given as percentages by weight.

The HFO-1234ze can be cis or trans form or be a mixture of these twoforms. It is preferably in trans (E) form.

According to the present application, the global warming potential (GWP)is defined with respect to carbon dioxide and with respect to a periodof 100 years, according to the method indicated in “The scientificassessment of ozone depletion, 2002, a report of the WorldMeteorological Association's Global Ozone Research and MonitoringProject”.

The term “heat-transfer compound”, respectively “heat-transfer fluid”(or refrigerant) is intended to mean a compound, respectively a fluid,capable of absorbing heat by evaporating at low temperature and lowpressure and of releasing heat by condensing at high temperature andhigh pressure, in a vapor compression circuit. In general, aheat-transfer fluid can comprise one, two, three or more than threeheat-transfer compounds.

The term “heat-transfer composition” is intended to mean a compositioncomprising a heat-transfer fluid and, optionally, one or more additiveswhich are not heat-transfer compounds for the intended application.

The additives can in particular be chosen from lubricants, stabilizers,surfactants, tracers, fluorescent agents, odorous agents andsolubilizing agents.

The stabilizer(s), when they are present, preferably represent at most5% by weight in the heat-transfer composition. Among the stabilizers,mention may in particular be made of nitromethane, ascorbic acid,terephthalic acid, azoles such as tolutriazole or benzotriazole,phenolic compounds such as tocopherol, hydroquinone, t-butylhydroquinone, 2,6-di-tert-butyl-4-methylphenol, epoxides (optionallyfluorinated or perfluorinated alkyl or alkenyl or aromatic) such asn-butyl glycidyl ether, hexanediol diglycidyl ether, allyl glycidylether, butylphenyl glycidyl ether, phosphites, phosphonates, thiols andlactones.

As lubricants, use may in particular be made of oils of mineral origin,silicone oils, paraffins of natural origin, naphthenes, syntheticparaffins, alkylbenzenes, poly-alpha-olefins, polyalkene glycols, polyolesters and/or polyvinyl ethers.

As tracers (capable of being detected), mention may be made ofdeuterated or nondeuterated hydrofluorocarbons, deuterated hydrocarbons,perfluorocarbons, fluoroethers, brominated compounds, iodinatedcompounds, alcohols, aldehydes, ketones, nitrous oxide and combinationsthereof. The tracer is different than the heat-transfer compound(s) ofwhich the heat-transfer fluid is composed.

As solubilizing agents, mention may be made of hydrocarbons, dimethylether, polyoxyalkylene ethers, amides, ketones, nitriles, chlorocarbons,esters, lactones, aryl ethers, fluoroethers and 1,1,1-trifluoroalkanes.The solubilizing agent is different than the heat-transfer compound(s)of which the heat-transfer fluid is composed.

As fluorescent agents, mention may be made of naphthalimides, perylenes,coumarins, anthracenes, phenanthracenes, xanthenes, thioxanthenes,naphthoxanthenes, fluoresceins and derivatives and combinations thereof.

As odorous agents, mention may be made of alkyl acrylates, allylacrylates, acrylic acids, acryl esters, alkyl ethers, alkyl esters,alkynes, aldehydes, thiols, thioethers, disulfides,allylisothiocyanates, alkanoic acids, amines, norbornenes, norbornenederivatives, cyclohexene, heterocyclic aromatic compounds, ascaridole,o-methoxy(methyl)phenol and combinations thereof.

The heat-transfer process according to the invention is based on the useof equipment comprising a vapor compression circuit which contains aheat-transfer fluid. The heat-transfer process can be a process forheating or for cooling a fluid or a body.

The vapor compression circuit containing a heat-transfer fluid comprisesat least one evaporator, one compressor, one condenser and onepressure-reducing valve, and also lines for transporting theheat-transfer fluid between these elements. The evaporator and thecondenser comprise a heat exchanger that allows an exchange of heatbetween the heat-transfer fluid and another fluid or body.

As a compressor, use may in particular be made of a centrifugalcompressor with one or more stages or a centrifugal mini compressor.Rotary compressors, reciprocating compressors or screw compressors canalso be used. The compressor may be driven by an electric motor or by agas turbine (for example fed with the exhaust gases of a vehicle, formobile applications) or by gearing.

The equipment may comprise a turbine for generating electricity (Rankinecycle).

The equipment can also optionally comprise at least one heat-exchangefluid circuit used for transmitting heat (with or without a change ofstate) between the heat-transfer fluid circuit and the fluid or body tobe heated or cooled.

The equipment may also optionally comprise two (or more) vaporcompression circuits containing identical or distinct heat-transferfluids. For example, the vapor compression circuits may be coupledtogether.

The vapor compression circuit operates according to a conventional vaporcompression cycle. The cycle comprises the change of state of theheat-transfer fluid from a liquid phase (or liquid/vapor two phasestate) to a vapor phase at a relatively low pressure, then thecompression of the fluid in the vapor phase up to a relatively highpressure, the change of state (condensation) of the heat-transfer fluidof the vapor phase to the liquid phase at a relatively high pressure,and the reduction of the pressure in order to recommence the cycle.

In the case of a cooling process, heat from the fluid or from the bodythat is being cooled (directly or indirectly, via a heat-exchange fluid)is absorbed by the heat-transfer fluid, during the evaporation of thelatter, at a relatively low temperature compared with the surroundings.The cooling processes include air conditioning processes (with mobileequipment, for example in vehicles, or stationary equipment),refrigeration processes and freezing processes or cryogenic processes.

In the case of a heating process, heat is imparted (directly orindirectly, via a heat-exchange fluid) from the heat-transfer fluid,during the condensation thereof, to the fluid or the body that is beingheated, at a relatively high temperature compared with the surroundings.The equipment that makes it possible to implement the heat transfer iscalled, in this case, a “heat pump”.

It is possible to employ any type of heat exchanger for using theheat-transfer fluids according to the invention, and in particularconcurrent heat exchangers or, preferably, countercurrent heatexchangers.

The heat-transfer fluids used in the context of the present inventionare compositions which comprise HFO-E-1336mzz in combination with atleast one hydrocarbon, ether, hydrofluoroether, hydrofluorocarbon orfluoroolefin compound (preferably a hydrofluorocarbon or fluoroolefincompound) with a boiling point less than or equal to −12° C. at apressure of 101.325 kPa.

The boiling point can be measured according to standard NF EN 378-1 ofApril 2008.

HC-600a has a boiling point greater than −12° C. and is not thereforeinvolved.

Preferably, the compound is chosen from HFO-1234yf, HFO-1234ze,HFO-1243zf, HFC-134a, HFC-32, HFC-152a, HFC-125, DME and HC-290.

In particular, the compositions above can be binary or ternary mixturesof compounds. In the case of the ternary mixtures, the heat-transferfluid can comprise HFO-E-1336mzz in combination with two compoundschosen from HFO-1234yf, HFO-1234ze, HFO-1243zf, HFC-134a, HFC-32,HFC-152a, HFC-125, DME and HC-290; or else HFO-E-1336mzz in combinationwith a compound chosen from HFO-1234yf, HFO-1234ze, HFO-1243zf,HFC-134a, HFC-32, HFC-152a, HFC-125, DME and HC-290 and also anadditional compound, preferably chosen from hydrocarbons,hydrochlorofluorocarbons, hydrofluorocarbons, fluoroethers, hydrocarbonethers, ammonia and carbon dioxide, and more particularly preferablyHC-600a.

According to one embodiment, the compositions above contain no HC-600a,optionally no HC-290, and optionally no hydrocarbon.

According to one embodiment, the compositions above comprise onlyfluoroolefins and/or hydrofluorocarbons.

Among the compositions above, some have the advantage of beingazeotrope-like.

The term “azeotrope-like” denotes compositions for which, at constanttemperature, the liquid saturation pressure and the vapor saturationpressure are virtually identical (the maximum pressure difference being10%, or even advantageously 5%, relative to the liquid saturationpressure). These heat-transfer fluids have an advantage in that they areeasy to use. In the absence of any significant temperature glide, thereis no significant change in the circulating composition, and nosignificant change either in the composition in the event of a leak.

In particular, the binary or ternary mixtures which have the followingcompositions are azeotrope-like at a reference temperature of −5° C.:

-   from 1% to 8% of HFO-E-1336mzz and from 92% to 99% of HFO-1234yf;-   from 1% to 12% of HFO-E-1336mzz and from 88% to 99% of HFO-1234ze;    or-   from 1% to 9% of HFO-E-1336mzz and from 91% to 99% of HFC-134a; or-   from 1% to 6% of HFO-E-1336mzz and from 94% to 99% of HFC-32; or-   from 1% to 17% of HFO-E-1336mzz and from 83% to 99% of HFC-152a; or-   from 1% to 26% of HFO-E-1336mzz and from 74% to 99% of HC-290; or-   from 1% to 10% of HFO-E-1336mzz and from 90% to 99% of HFO-1243zf;    or-   from 1% to 10% of HFO-E-1336mzz, from 1% to 98% of HFC-134a and from    1% to 98% of HFO-1234ze; or-   from 1% to 8% of HFO-E-1336mzz, from 1% to 98% of HFC-134a and from    1% to 98% of HFO-1234yf; or-   from 1% to 15% of HFO-E-1336mzz, from 1% to 98% of HFC-134a and from    1% to 98% of HFC-152a; or-   from 1% to 8% of HFO-E-1336mzz, from 1% to 98% of HFO-1234yf and    from 1% to 98% of HFO-1243zf; or-   from 1% to 8% of HFO-E-1336mzz, from 1% to 98% of HFC-134a and from    1% to 98% of HFO-1243zf; or-   from 1% to 8% of HFO-E-1336mzz, from 1% to 98% of HFO-1234yf and    from 1% to 98% of HFO-1234ze; or-   from 1% to 20% of HFO-E-1336mzz, from 1% to 30% of HFC-134a and from    50% to 98% of HC-290; or-   from 1% to 20% of HFO-E-1336mzz, from 1% to 98% of HFO-1234yf and    from 1% to 98% of HC-290; or-   from 1% to 13% of HFO-E-1336mzz, from 1% to 98% of HFO-1234yf and    from 1% to 98% of HFC-152a; or-   from 1% to 15% of HFO-E-1336mzz, from 1% to 98% of HFO-1234ze and    from 1% to 98% of HFC-152a; or-   from 1% to 20% of HFO-E-1336mzz, from 1% to 98% of HFO-1234ze and    from 1% to 98% of HC-290.

In addition it has been found that certain compositions according to theinvention have improved performance levels compared with HFO-1234ze, andwhich are close to those of HC-600a, in particular for processes forcooling or for heating at moderate temperature, i.e. those in which thetemperature of the fluid or of the body cooled is from −15° C. to 15°C., preferably from −10° C. to 10° C. and more particularly preferablyfrom −5° C. to 5° C. (ideally approximately 0° C.). These compositionsare in particular the following binary or ternary mixtures:

-   from 10% to 50% of HFO-E-1336mzz and from 50% to 90% of HFO-1234ze    (in particular from 30% to 40% of HFO-E-1336mzz and from 60% to 70%    of HFO-1234ze);-   from 55% to 95% of HFO-E-1336mzz and from 5% to 45% of HFC-134a;-   from 1% to 98% of HFO-E-1336mzz, from 1% to 98% of HFO-1234ze and    from 1% to 40% of HFC-134a, preferably 2% to 40% of HFO-E-1336mzz,    from 20% to 93% of HFO-1234ze and from 5% to 40% of HFC-134a and    more particularly preferably from 2% to 35% of HFO-E-1336mzz, from    33% to 89% of HFO-1234ze and from 9% to 32% of HFC-134a;-   from 1% to 98% of HFO-E-1336mzz, from 1% to 98% of HFO-1234yf and    from 1% to 50% of HFC-134a, preferably from 2% to 60% of    HFO-E-1336mzz, from 2% to 93% of HFO-1234yf and from 5% to 50% of    HFC-134a and particularly preferably from 5% to 45% of    HFO-E-1336mzz, from 11% to 86% of HFO-1234yf and from 9% to 44% of    HFC-134a.

In the processes for “cooling or heating at moderate temperature”mentioned above, the inlet temperature of the heat-transfer fluid at theevaporator is preferably from −20° C. to 10° C., in particular from −15°C. to 5° C., more particularly preferably from −10° C. to 0° C. and forexample approximately −5° C.; and the temperature at the beginning ofthe condensation of the heat-transfer fluid at the condenser ispreferably from 25° C. to 90° C., in particular from 30° C. to 70° C.,more particularly preferably from 35° C. to 55° C. and for exampleapproximately 50° C. These processes can be refrigeration processes, airconditioning processes or heating processes.

The compositions according to the invention can also be of use as ablowing agent, an aerosol or a solvent.

EXAMPLES

The following examples illustrate the invention without limiting it.

Example 1 Method for Calculating the Properties of the Heat-TransferFluids in the Various Configurations Envisaged

The RK-Soave equation is used to calculate the densities, enthalpies,entropies and liquid/vapor equilibrium data of the mixtures. The use ofthis equation requires knowledge of the properties of the puresubstances used in the mixtures in question and also the interactioncoefficients for each binary mixture.

The data available for each pure substance are the boiling point, thecritical temperature and the critical pressure, the curve of pressure asa function of the temperature from the boiling point up to the criticalpoint, and the saturated liquid and saturated vapor densities as afunction of the temperature.

The data regarding HFCs are published in the Ashrae Handbook 2005,chapter 20, and are also available from Refrop (software developed byNIST for calculating the properties of refrigerants).

The HFO temperature-pressure curve data are measured by the staticmethod. The critical temperature and the critical pressure are measuredusing a C80 calorimeter sold by Setaram.

The RK-Soave equation uses coefficients of binary interaction torepresent the behavior of products in mixtures. The coefficients arecalculated as a function of the experimental liquid/vapor equilibriumdata.

The technique used for the liquid/vapor equilibrium measurements is thestatic analytical cell method. The equilibrium cell comprises a sapphiretube and is equipped with two Rolsitm electromagnetic samplers. It isimmersed in a cryothermostat bath (Huber HS40). Magnetic stirring drivenby a magnetic field rotating at a variable speed is used to acceleratethe reaching of the equilibria. The sample analysis is carried out bygas chromatography (HP5890 series II) using a catharometer (TCD).

The liquid/vapor equilibrium measurements on the binary mixtureHFC-134a/HFO-1234ze are carried out for the following isotherm: 20° C.

The liquid/vapor equilibrium measurements on the binary mixtureHFC-134a/HFO-1234yf are carried out for the following isotherm: 20° C.

The liquid/vapor equilibrium data for the binary mixtureHFO-1243zf/HFO-1234yf are produced for the following isotherm: 21° C.

The liquid/vapor equilibrium measurements on the binary mixtureHFC-134a/HFO-1243zf are carried out for the following isotherm: 10° C.

The liquid/vapor equilibrium measurements on the binary mixtureHFO-1234ze/HFO-1234yf are carried out for the following isotherm: 18° C.

The liquid/vapor equilibrium measurements on the binary mixtureHC-290/HFO-1234yf are carried out for the following isotherm: −10 and55° C.

The liquid/vapor equilibrium measurements on the binary mixtureHFC-152a/HFO-1234yf are carried out for the following isotherm: 10° C.

The liquid/vapor equilibrium measurements on the binary mixtureHFC-152a/HFO-1234ze are carried out for the following isotherm: 15° C.

The liquid/vapor equilibrium measurements on the binary mixtureHFC-134a/HFO-E-1336mzz are carried out for the following isotherm: 45°C.

The liquid/vapor equilibrium measurements on the binary mixtureHFC-32/HFO-E-1336mzz are carried out for the following isotherm: 45° C.

The liquid/vapor equilibrium measurements on the binary mixtureHFC-152a/HFO-E-1336mzz are carried out for the following isotherm: 45°C.

The liquid/vapor equilibrium measurements on the binary mixtureHC-290/HFO-E-1336mzz are carried out for the following isotherm: 45° C.

The liquid/vapor equilibrium measurements on the binary mixtureHFO-1234yf/HFO-E-1336mzz are carried out for the following isotherm: 45°C.

The liquid/vapor equilibrium measurements on the binary mixtureHFO-1243g/HFO-E-1336mzz are carried out for the following isotherm: 45°C.

The liquid/vapor equilibrium measurements on the binary mixtureHFO-1234ze/HFO-E-1336mzz are carried out for the following isotherm: 45°C.

For the evaluation of the energy performance levels, a compressionsystem equipped with a countercurrent evaporator and condenser, with ascrew compressor and with a pressure-reducing valve is considered.

The system operates with 5° C. of overheat. The evaporation temperatureis −5° C. and the condensation temperature is 50° C.

The coefficient of performance (COP) is defined as being the usefulpower supplied by the system over the power provided or consumed by thesystem.

The Lorenz coefficient of performance (COPLorenz) is a referencecoefficient of performance. It depends on temperatures and is used tocompare the COPs of the various fluids.

The Lorenz coefficient of performance is defined as follows (thetemperatures T are in K):

T _(average) ^(condenser) =T _(inlet) ^(condenser) −T _(outlet)^(condenser)

T _(average) ^(evaporator) =T _(outlet) ^(evaporator) −T _(inlet)^(evaporator)

The Lorenz COP in the case of conditioned air and of refrigeration is:

${COPlorenz} = \frac{T_{average}^{evaporator}}{T_{average}^{condenser} - T_{average}^{evaporator}}$

The Lorenz COP in the case of heating is:

${COPlorenz} = \frac{T_{average}^{condenser}}{T_{average}^{condenser} - T_{average}^{evaporator}}$

For each composition, the coefficient of performance of the Lorenz cycleis calculated as a function of the corresponding temperatures.

In the tables which follow, “Temp (° C.)” denotes the temperature, “Psat liquid” denotes the liquid saturation pressure, “P sat vapor”denotes the vapor saturation pressure, “Diff Pressure (%)” denotes theratio of the difference between the liquid saturation pressure and thevapor saturation pressure, over the liquid saturation pressure (as %),“Temp evap outlet” denotes the temperature of the fluid at the outlet ofthe evaporator, “Temp comp outlet” denotes the temperature of the fluidat the outlet of the compressor, “T cond outlet” denotes the temperatureof the fluid at the outlet of the condenser, “Temp press-red inlet”denotes the temperature of the fluid at the inlet of thepressure-reducing valve, “evap P (bar)” denotes the pressure of thefluid in the evaporator, “cond P (bar)” denotes the pressure of thefluid in the condenser, “Ratio (w/w)” denotes the compression ratio,“Glide” denotes the temperature glide, “% CAP” denotes the volumetriccapacity of the fluid relative to the reference fluid indicated on thefirst line, “% COP/COPLorenz” denotes the ratio of the COP of the systemrelative to the COP of the corresponding Lorenz cycle.

Example 2 Data for the Azeotrope-Like Mixtures

HFO-1234yf/HFO-E-1336mzz mixture:

Composition (%) Diff. HFO-E- P sat. P sat. pressure HFO-1234yf 1336mzzTemp. (° C.) liquid vapor (%) 98 2 −5 2.6 2.5 3 96 4 −5 2.6 2.4 6 94 6−5 2.5 2.3 8 93 7 −5 2.5 2.3 9

HFO-1234ze/HFO-E-1336mzz mixture:

Composition (%) Diff. HFO- HFO-E- P sat. P sat. pressure 1234ze 1336mzzTemp. (° C.) liquid vapor (%) 96 4 −5 1.7 1.7 4 95 5 −5 1.7 1.7 4 91 9−5 1.7 1.6 8 90 10 −5 1.7 1.5 8 89 11 −5 1.7 1.5 9 88 12 −5 1.7 1.5 10

HFC-134a/HFO-E-1336mz mixture:

Composition (%) Diff. HFO-E- P sat. P sat. pressure HFC-134a 1336mzzTemp. (° C.) liquid vapor (%) 96 4 −5 2.4 2.3 4 95 5 −5 2.4 2.2 5 91 9−5 2.3 2.1 10

HFC-32/HFO-E-1336mz mixture:

Composition (%) Diff. HFO-E- P sat. P sat. pressure HFC-32 1336mzz Temp.(° C.) liquid vapor (%) 99 1 −5 6.9 6.8 2 98 2 −5 6.9 6.6 3 96 4 −5 6.86.3 7 95 5 −5 6.8 6.2 9

HFC-152a/HFO-E-1336mzz mixture:

Composition (%) Diff. HFO-E- P sat. P sat. pressure HFC-152a 1336mzzTemp. (° C.) liquid vapor (%) 98 2 −5 2.2 2.2 1 96 4 −5 2.2 2.1 2 94 6−5 2.2 2.1 4 92 8 −5 2.1 2.0 5 90 10 −5 2.1 2.0 6 88 12 −5 2.1 2.0 7 8614 −5 2.1 1.9 8 84 16 −5 2.1 1.9 9

HC-290/HFO-E-1336mzz mixture:

Composition (%) Diff. HFO-E- P sat. P sat. pressure HC-290 1336mzz Temp.(° C.) liquid vapor (%) 98 2 −5 4.0 4.0 0 96 4 −5 4.0 4.0 0 94 6 −5 4.04.0 1 92 8 −5 4.0 4.0 1 90 10 −5 4.0 4.0 1 85 15 −5 4.0 3.9 3 80 20 −53.9 3.7 5 75 25 −5 3.9 3.6 9

HFO-1243g/HFO-E-1336mzz mixture:

Composition (%) Diff. HFO-E- P sat. P sat. pressure HFO-1243zf 1336mzzTemp. (° C.) liquid vapor (%) 98 2 −5 2.3 2.2 2 96 4 −5 2.2 2.1 4 94 6−5 2.2 2.1 6 93 7 −5 2.2 2.1 7 92 8 −5 2.2 2.0 8 90 10 −5 2.2 2.0 10

HFC-134a/HFO-1234ze/HFO-E-1336mzz mixture:

Composition (%) Diff. HFC- HFO- HFO-E- Temp. P sat. P sat. pressure 134a1234ze 1336mzz (° C.) liquid vapor (%) 3 90 7 −5 1.7 1.6 7 10 83 7 −51.8 1.7 8 20 73 7 −5 1.9 1.7 9 30 63 7 −5 2.0 1.8 10 40 53 7 −5 2.1 1.910 50 43 7 −5 2.1 1.9 10 3 89 8 −5 1.7 1.6 8 10 82 8 −5 1.8 1.6 9 20 728 −5 1.9 1.7 10 3 88 9 −5 1.7 1.6 8 10 81 9 −5 1.8 1.6 10 3 87 10 −5 1.71.6 9

HFC-134a/HFO-1234yf/HFO-E-1336mzz mixture:

Composition (%) Diff. HFC- HFO- HFO-E- Temp. P sat. P sat. pressure 134a1234yf 1336mzz (° C.) liquid vapor (%) 2 93 5 −5 2.6 2.4 7 10 85 5 −52.6 2.4 8 15 80 5 −5 2.6 2.4 8 20 75 5 −5 2.6 2.4 8 25 70 5 −5 2.6 2.4 830 65 5 −5 2.6 2.4 8 40 55 5 −5 2.6 2.4 8 50 45 5 −5 2.6 2.4 8 60 35 5−5 2.6 2.4 8 70 25 5 −5 2.5 2.4 8 80 15 5 −5 2.5 2.3 7 90 5 5 −5 2.4 2.36 5 89 6 −5 2.6 2.3 9 10 84 6 −5 2.6 2.4 9 20 74 6 −5 2.6 2.4 9 30 64 6−5 2.6 2.4 9 40 54 6 −5 2.6 2.4 9 50 44 6 −5 2.6 2.4 9 60 34 6 −5 2.62.3 9 70 24 6 −5 2.5 2.3 9 80 14 6 −5 2.5 2.3 8 90 4 6 −5 2.4 2.2 7 5 887 −5 2.6 2.3 10 10 83 7 −5 2.6 2.3 10 60 33 7 −5 2.6 2.3 10 70 23 7 −52.5 2.3 10 80 13 7 −5 2.5 2.2 9 90 3 7 −5 2.4 2.2 8

HFC-134a/HFC-152a/HFO-E-1336mzz mixture:

Composition (%) Diff. HFC- HFC- HFO-E- Temp. P sat. P sat. pressure 134a152a 1336mzz (° C.) liquid vapor (%) 5 87 8 −5 2.1 2.0 5 10 82 8 −5 2.12.0 5 20 72 8 −5 2.1 2.0 5 30 62 8 −5 2.2 2.0 5 50 42 8 −5 2.2 2.1 6 7022 8 −5 2.2 2.1 6 90 2 8 −5 2.3 2.1 8 5 83 12 −5 2.1 2.0 7 10 78 12 −52.1 2.0 7 20 68 12 −5 2.1 2.0 7 30 58 12 −5 2.1 2.0 8 60 28 12 −5 2.22.0 9 5 80 15 −5 2.1 1.9 9 10 75 15 −5 2.1 1.9 9 20 65 15 −5 2.1 1.9 930 55 15 −5 2.1 1.9 10 40 45 15 −5 2.1 1.9 10

HFC-134a/HFO-1243g/HFO-E-1336mzz mixture:

Composition (%) Diff. HFC- HFO- HFO-E- Temp. P sat. P sat. pressure 134a1243zf 1336mzz (° C.) liquid vapor (%) 5 87 8 −5 2.2 2.0 8 10 82 8 −52.2 2.0 8 20 72 8 −5 2.3 2.1 8 30 62 8 −5 2.3 2.1 9 40 52 8 −5 2.3 2.1 950 42 8 −5 2.3 2.1 9 60 32 8 −5 2.3 2.1 9 70 22 8 −5 2.3 2.1 9 80 12 8−5 2.3 2.1 9 90 2 8 −5 2.3 2.1 9

HFC-134a/HC-290/HFO-E-1336mzz mixture:

Composition (%) Diff. HFC- HFO-E- Temp. P sat. P sat. pressure 134aHC-290 1336mzz (° C.) liquid vapor (%) 5 86 9 −5 4.2 4.0 3 10 81 9 −54.3 4.1 5 20 71 9 −5 4.5 4.2 7 5 80 15 −5 4.1 3.9 5 10 75 15 −5 4.2 3.97 5 75 20 −5 4.1 3.8 8

HFO-1234yf/HFO-1234ze/HFO-E-1336mzz mixture:

Composition (%) Diff. HFO- HFO- HFO-E- Temp. P sat. P sat. pressure1234yf 1234ze 1336mzz (° C.) liquid vapor (%) 5 90 5 −5 1.8 1.7 6 15 805 −5 1.9 1.8 8 25 70 5 −5 2.0 1.8 9 35 60 5 −5 2.1 1.9 10 10 82 8 −5 1.81.6 10

HFC-1234yf/HC-290/HFO-E-1336mzz mixture:

Composition (%) Diff. HFO- HFO-E- Temp. P sat. P sat. pressure 1234yfHC-290 1336mzz (° C.) liquid vapor (%) 10 82 8 −5 4.1 4.0 2 20 72 8 −54.2 4.1 3 30 62 8 −5 4.3 4.1 4 40 52 8 −5 4.3 4.0 6 50 42 8 −5 4.3 3.910 10 78 12 −5 4.1 4.0 4 20 68 12 −5 4.2 4.0 5 30 58 12 −5 4.3 3.9 8 575 20 −5 4.0 3.7 7 10 70 20 −5 4.0 3.7 9

HFO-1234yf/HFO-1243zf/HFO-E-1336mzz mixture:

Composition (%) Diff. HFO- HFO- HFO-E- Temp. P sat. P sat. pressure1234yf 1243zf 1336mzz (° C.) liquid vapor (%) 10 82 8 −5 2.2 2.0 8 20 728 −5 2.3 2.1 9 30 62 8 −5 2.3 2.1 9 40 52 8 −5 2.3 2.1 9 50 42 8 −5 2.42.1 10 60 32 8 −5 2.4 2.2 10 70 22 8 −5 2.4 2.2 10 80 12 8 −5 2.5 2.2 10

HC-290/HFO-1234ze/HFO-E-1336mzz mixture:

Composition (%) Diff. HFO- HFO-E- Temp. P sat. P sat. pressure HC-2901234ze 1336mzz (° C.) liquid vapor (%) 70 20 10 −5 3.8 3.4 9 80 10 10 −53.9 3.7 5 85 5 10 −5 4.0 3.8 3 75 5 20 −5 3.9 3.6 8

HFO-1234yf/HFC-152a/HFO-E-1336mzz mixture:

Composition (%) Diff. HFO- HFC- HFO-E- Temp. P sat. P sat. pressure1234yf 152a 1336mzz (° C.) liquid vapor (%) 90 5 5 −5 3 2 7 60 35 5 −5 32 7 50 45 5 −5 3 2 7 40 55 5 −5 2 2 7 20 75 5 −5 2 2 6 10 85 5 −5 2 2 530 60 10 −5 2 2 10 20 70 10 −5 2 2 9 10 80 10 −5 2 2 8 7 80 13 −5 2 2 92 85 13 −5 2 2 8

HFO-1234ze/HFC-152a/HFO-E-1336mzz mixture:

Composition (%) Diff. HFO- HFC- HFO-E- Temp. P sat. P sat. pressure1234ze 152a 1336mzz (° C.) liquid vapor (%) 90 5 5 −5 1.8 1.7 5 70 25 5−5 2.0 1.8 6 50 45 5 −5 2.0 1.9 5 30 65 5 −5 2.1 2.0 4 10 85 5 −5 2.22.1 3 85 5 10 −5 1.7 1.6 9 75 15 10 −5 1.8 1.7 10 65 25 10 −5 1.9 1.7 1040 50 10 −5 2.0 1.9 8 30 60 10 −5 2.1 1.9 8 20 70 10 −5 2.1 1.9 7 10 8010 −5 2.1 2.0 7 15 70 15 −5 2.1 1.9 10 5 80 15 −5 2.1 1.9 9

Example 3 Results for a Refrigeration at Moderate Temperature,Comparison with HFO-1234ze

HFO-1234ze/HFO-E-1336mzz mixture:

T cond Composition Temp evap. Temp comp outlet Temp pressred evap P condP Ratio Comp % COP/ (%) outlet (° C.) outlet (° C.) (° C.) inlet (° C.)(bar) (bar) (w/w) Glide efficiency % CAP COPLorenz HFO-1234ze −5 63 5047 1.8 10.0 5.6 0.00 74.8 100 53 HFO-E- HFO-1234ze 1336mzz 95 5 −4 62 4947 1.7 9.6 5.6 0.94 75.1 99 53 85 15 −3 61 48 45 1.6 8.8 5.5 2.43 75.495 54 75 25 −2 60 47 44 1.5 8.1 5.5 3.49 75.5 90 55 65 35 −1 59 46 431.3 7.4 5.5 4.16 75.4 85 55

HFC-134a/HFO-E-1336mzz mixture:

T cond Composition Temp evap. Temp comp outlet Temp pressred evap P condP Ratio Comp % COP/ (%) outlet (° C.) outlet (° C.) (° C.) inlet (° C.)(bar) (bar) (w/w) Glide efficiency % CAP COPLorenz HFO-1234ze −5 63 5047 1.8 10.0 5.6 0.00 74.8 100 53 HFO-E- HFC-134a 1336mzz 95 5 −4 70 4947 2.4 12.6 5.3 1.24 76.3 137 55 85 15 −1 68 47 45 2.2 11.4 5.2 3.5876.9 132 57 75 25 1 66 45 43 2.0 10.3 5.0 5.53 77.5 127 58 65 35 2 64 4341 1.9 9.2 5.0 7.01 77.9 120 59 55 45 3 61 42 39 1.7 8.2 4.9 7.91 78.0112 60 45 55 3 59 41 38 1.5 7.3 5.0 8.14 77.7 101 60 35 65 3 58 40 381.3 6.5 5.2 7.59 76.9 89 60 25 75 1 56 41 38 1.0 5.8 5.6 6.14 75.0 74 58

HFC-134a/HFO-1234ze/HFO-E-1336mzz mixture:

Temp Temp Temp evap. comp T cond pressred Composition outlet outletoutlet inlet evap P cond P Ratio Comp % COP/ (%) (° C.) (° C.) (° C.) (°C.) (bar) (bar) (w/w) Glide efficiency % CAP COPLorenz HFO-1234ze −5 6350 47 1.8 10.0 5.6 0.00 74.8 100 53 HFO- HFO-E- HFC-134a 1234ze 1336mzz10 70 20 −1 61 46 44 1.6 8.7 5.4 3.51 76.0 99 55 10 65 25 −1 61 46 431.6 8.4 5.4 4.05 76.0 97 56 10 60 30 −1 60 45 43 1.5 8.0 5.4 4.50 76.194 56 10 55 35 0 60 45 42 1.4 7.7 5.4 4.86 76.0 92 56 15 70 15 −2 62 4744 1.7 9.3 5.4 3.06 76.0 104 55 15 65 20 −1 62 46 44 1.7 8.9 5.4 3.7176.1 101 55 15 60 25 −1 61 46 43 1.6 8.5 5.3 4.29 76.3 100 56 15 55 30 060 45 42 1.5 8.2 5.3 4.77 76.3 97 56 20 70 10 −3 63 48 45 1.8 9.9 5.42.40 75.9 108 55 20 65 15 −2 63 47 44 1.8 9.4 5.4 3.21 76.2 106 55 20 6020 −1 62 46 44 1.7 9.1 5.3 3.90 76.3 104 56 20 55 25 0 62 45 43 1.6 8.75.3 4.51 76.5 103 56 30 65 5 −3 65 48 46 2.0 10.7 5.4 1.59 75.8 114 5430 60 10 −2 64 47 45 1.9 10.2 5.4 2.59 76.1 113 55 30 55 15 −2 63 47 441.8 9.8 5.3 3.45 76.4 111 56 40 55 5 −3 65 48 46 2.0 11.0 5.4 1.65 75.9118 55 40 50 10 −2 65 47 45 2.0 10.5 5.3 2.70 76.3 117 55 40 45 15 −1 6447 44 1.9 10.1 5.3 3.61 76.6 116 56

HFC-134a/HFO-1234yf/HFO-E-1336mzz mixture:

Temp Temp Temp evap. comp T cond pressred Composition outlet outletoutlet inlet evap P cond P Ratio Comp % COP/ (%) (° C.) (° C.) (° C.) (°C.) (bar) (bar) (w/w) Glide efficiency % CAP COPLorenz HFO-1234ze −5 6350 47 1.8 10.0 5.6 0.00 74.8 100 53 HFO- HFO-E- 1234yf HFC-134a 1336mzz60 10 30 3 58 44 41 2.0 9.4 4.6 7.55 79.1 120 58 55 10 35 3 58 43 40 1.98.9 4.6 8.14 79.2 117 59 50 10 40 4 57 42 39 1.8 8.4 4.6 8.56 79.1 11359 45 10 45 4 57 41 38 1.7 7.9 4.7 8.80 79.0 108 59 60 15 25 2 59 44 422.2 10.0 4.6 6.86 79.1 124 57 55 15 30 3 59 44 41 2.0 9.4 4.6 7.63 79.2121 58 50 15 35 3 58 43 40 1.9 8.9 4.6 8.21 79.2 118 59 45 15 40 4 58 4239 1.8 8.4 4.6 8.62 79.1 114 59 55 20 25 2 60 44 42 2.2 10.0 4.6 6.9179.1 126 57 50 20 30 3 59 43 41 2.1 9.5 4.6 7.67 79.1 123 58 45 20 35 359 43 40 1.9 9.0 4.6 8.25 79.2 119 59 40 20 40 4 58 42 39 1.8 8.5 4.68.65 79.1 115 59 60 30 10 −1 62 48 45 2.5 11.9 4.8 3.53 78.6 134 55 5530 15 0 61 46 44 2.4 11.3 4.7 4.87 78.8 132 56 50 30 20 1 61 45 43 2.310.7 4.7 5.98 78.9 130 57 45 30 25 2 61 44 42 2.2 10.1 4.7 6.90 79.0 12758 55 40 5 −3 63 49 46 2.6 12.7 4.9 1.93 78.2 136 54 50 40 10 −2 63 4845 2.5 12.0 4.8 3.49 78.4 135 55 45 40 15 0 62 47 44 2.4 11.4 4.8 4.8078.6 133 56

1. A composition comprising (E)-1,1,1,4,4,4-hexafluorobut-2-ene and atleast one compound having a boiling point less than or equal to −12° C.at a pressure of 101.325 KPa selected from the group consisting of anether, a hydrofluoroether and a fluoroolefin. 2-3. (canceled)
 4. Thecomposition as claimed in claim 1, wherein the composition comprises amixture selected from the group consisting of:(E)-1,1,1,4,4,4-hexafluorobut-2-ene, 1,1,1,2-tetrafluoroethane and1,3,3,3-tetrafluoropropene; (E)-1,1,1,4,4,4-hexafluorobut-2-ene,1,1,1,2-tetrafluoroethane and 2,3,3,3-tetrafluoropropene;(E)-1,1,1,4,4,4-hexafluorobut-2-ene, 1,1,1,2-tetrafluoroethane and3,3,3-trifluoropropene; (E)-1,1,1,4,4,4-hexafluorobut-2-ene, isobutaneand 1,3,3,3-tetrafluoropropene; (E)-1,1,1,4,4,4-hexafluorobut-2-ene,isobutane and 2,3,3,3-tetrafluoropropene;(E)-1,1,1,4,4,4-hexafluorobut-2-ene, isobutane and 1,1-difluoroethane;(E)-1,1,1,4,4,4-hexafluorobut-2-ene, isobutane and propane;(E)-1,1,1,4,4,4-hexafluorobut-2-ene, 3,3,3-trifluoropropene and2,3,3,3-tetrafluoropropene; (E)-1,1,1,4,4,4-hexafluorobut-2-ene,3,3,3-trifluoropropene and 1,3,3,3-tetrafluoropropene;(E)-1,1,1,4,4,4-hexafluorobut-2-ene, 3,3,3-trifluoropropene andisobutane; (E)-1,1,1,4,4,4-hexafluorobut-2-ene, 3,3,3-trifluoropropeneand 1,1-difluoroethane; (E)-1,1,1,4,4,4-hexafluorobut-2-ene,3,3,3-trifluoropropene and propane; (E)-1,1,1,4,4,4-hexafluorobut-2-ene,1,3,3,3-tetrafluoropropene and 2,3,3,3-tetrafluoropropene;(E)-1,1,1,4,4,4-hexafluorobut-2-ene, 1,3,3,3-tetrafluoropropene andpropane; (E)-1,1,1,4,4,4-hexafluorobut-2-ene, 1,3,3,3-tetrafluoropropeneand 1,1-difluoroethane; (E)-1,1,1,4,4,4-hexafluorobut-2-ene,2,3,3,3-tetrafluoropropene and propane;(E)-1,1,1,4,4,4-hexafluorobut-2-ene, 2,3,3,3-tetrafluoropropene and1,1-difluoroethane; (E)-1,1,1,4,4,4-hexafluorobut-2-ene,pentafluoroethane and 1,3,3,3-tetrafluoropropene;(E)-1,1,1,4,4,4-hexafluorobut-2-ene, pentafluoroethane and2,3,3,3-tetrafluoropropene; and (E)-1,1,1,4,4,4-hexafluorobut-2-ene,pentafluoroethane and 3,3,3-trifluoropropene.
 5. The composition asclaimed in claim 1, wherein the difference between the liquid saturationpressure and the vapor saturation pressure at a temperature of −5° C. isless than or equal to 10% of the liquid saturation pressure, and whereinthe composition comprises: from 1% to 8% of(E)-1,1,1,4,4,4-hexafluorobut-2-ene and from 92% to 99% of2,3,3,3-tetrafluoropropene; or from 1% to 12% of(E)-1,1,1,4,4,4-hexafluorobut-2-ene and from 88% to 99% of1,3,3,3-tetrafluoropropene; or from 1% to 9% of(E)-1,1,1,4,4,4-hexafluorobut-2-ene and from 91% to 99% of1,1,1,2-tetrafluoroethane; or from 1% to 6% of(E)-1,1,1,4,4,4-hexafluorobut-2-ene and from 94% to 99% ofdifluoromethane; or from 1% to 17% of(E)-1,1,1,4,4,4-hexafluorobut-2-ene and from 83% to 99% of1,1-difluoroethane; or from 1% to 26% of(E)-1,1,1,4,4,4-hexafluorobut-2-ene and from 74% to 99% of propane; orfrom 1% to 10% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene and from 90% to99% of 3,3,3-trifluoropropene; or from 1% to 10% of(E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 1% to 98% of1,1,1,2-tetrafluoroethane and from 1% to 98% of1,3,3,3-tetrafluoropropene; or from 1% to 8% of(E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 1% to 98% of1,1,1,2-tetrafluoroethane and from 1% to 98% of2,3,3,3-tetrafluoropropene; or from 1% to 8% of(E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 1% to 98% of2,3,3,3-tetrafluoropropene and from 1% to 98% of 3,3,3-trifluoropropene;or from 1% to 8% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 1% to 98%of 1,1,1,2-tetrafluoroethane and from 1% to 98% of3,3,3-trifluoropropene; or from 1% to 8% of(E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 1% to 98% of2,3,3,3-tetrafluoropropene and from 1% to 98% of1,3,3,3-tetrafluoropropene; or from 1% to 20% of(E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 1% to 98% of2,3,3,3-tetrafluoropropene and from 1% to 98% of propane; or from 1% to13% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 1% to 98% of2,3,3,3-tetrafluoropropene and from 1% to 98% of 1,1-difluoroethane; orfrom 1% to 15% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 1% to 98% of1,3,3,3-tetrafluoropropene and from 1% to 98% of 1,1-difluoroethane; orfrom 1% to 20% of (E)-1,1,1,4,4,4-hexafluorobut-2-ene, from 1% to 98% of1,3,3,3-tetrafluoropropene and from 1% to 98% of propane.
 6. (canceled)7. (canceled)
 8. A heat-transfer composition comprising the compositionas claimed in claim 1 and also one or more additives chosen fromlubricants, stabilizers, surfactants, tracers, fluorescent agents,odorous agents and solubilizing agents, and mixtures thereof. 9.Heat-transfer equipment comprising a vapor compression circuitcontaining a composition as claimed in claim
 1. 10. The heat-transferequipment as claimed in claim 9, selected from mobile heat-pump heatingor stationary heat-pump heating, air conditioning, refrigerationequipment and freezing equipment, and Rankine cycles.
 11. A process forheating or cooling a fluid or a body by means of a vapor compressioncircuit containing a heat-transfer fluid, said process successivelycomprising evaporation of the heat-transfer fluid, compression of theheat-transfer fluid, condensation of the heat-transfer fluid andexpansion of the heat-transfer fluid, wherein the heat-transfer fluid isa composition as claimed in claim
 1. 12. The process as claimed in claim11, comprising a process for cooling a fluid or a body, wherein thetemperature of the fluid or of the body cooled is from −15° C. to 15° C.13. A process for reducing the environmental impact of heat-transferequipment comprising a vapor compression circuit containing an initialheat-transfer fluid, said process comprising a step replacing theinitial heat-transfer fluid in the vapor compression circuit with afinal heat-transfer fluid, the final heat-transfer fluid having a GWPwhich is lower than the initial heat-transfer fluid, wherein the finalheat-transfer fluid is a composition as claimed in claim
 1. 14. Thecomposition of claim 1, wherein the difference between the liquidsaturation pressure and the vapor saturation pressure at a temperatureof −5° C. is less than or equal to 10% of the liquid saturationpressure.
 15. The composition as claimed in claim 14, wherein thedifference between the liquid saturation pressure and the vaporsaturation pressure at a temperature of −5° C. is less than or equal to5% of the liquid saturation pressure.
 16. The composition as claimed inclaim 1, wherein the at least one compound includes an ether.
 17. Thecomposition as claimed in claim 1, wherein the at least one compoundincludes a hydrofluoroether.
 18. The composition as claimed in claim 1,wherein the at least one compound includes a fluoroolefin.
 19. Theprocess as claimed in claim 12, comprising a process for cooling a fluidor a body, wherein the temperature of the fluid or of the body cooled isfrom −10° C. to 10° C.
 20. The process as claimed in claim 19,comprising a process for cooling a fluid or a body, wherein thetemperature of the fluid or of the body cooled is from −5° C. to 5° C.21. The process as claimed in claim 11, comprising a process for heatinga fluid or a body, wherein the temperature of the fluid or of the bodyheated is from 30° C. to 90° C.
 22. The process as claimed in claim 21,comprising a process for heating a fluid or a body, wherein thetemperature of the fluid or of the body heated is from 35° C. to 60° C.23. The process as claimed in claim 22, comprising a process for heatinga fluid or a body, wherein the temperature of the fluid or of the bodyheated is from 40° C. to 50° C.
 24. The heat-transfer equipment asclaimed in claim 9, wherein the vapor-compression circuit comprises acentrifugal compressor.
 25. Equipment comprising a vapor compressioncircuit containing a composition as claimed in claim 1, wherein thevapor-compression circuit comprises a turbine.